Electric apparatus



March 25 1924; 1,488,310 c. A. BIRCH-FIELD 4 4 ELECTRIC APPARATUS Filed Sept. 26 1922 A TTORNJ? Patented Mar. 25, 1924.

PATENT OFFICE.

CHARLES A. man-memo: L'AncHMoN'r, NEW YORK.

nnncrnrc arramcros.

Application filed September as, 1922. Serial No. 550,561.

To all whom it may concern: 1

Be it known that 1, CHARLES A. BIRCH- FIELD, a citizen of the United States residing at Larchmont, county of Westchester, State of New .York, have made a. certain new and useful Invention-in Electric Apparatus, of'which. thenfollowing is a specification." T This invention relates generally to elec-: tric apparatus and more particularly to the utilization of such apparatus for the recep tion of impulses atT-radio frequencies'and their conversion into impulses. at audiov freauencies. hile my apparatus as a whole is:inteiid-' ed" for utilization in comiection' 'with" the reception ofelectric 'impuls'es 'a't radio .fre-u quencies,v it -.vvill,-be understood-- or course that elements: andiarts thereof are;fca---- pable 1 bf utility r in Ere ationship's 1 other than thatzhrein pointedout; andi'as-to such others relationships,- a'the. embodiment shown in r the i 1 drawings.-':1s;-; intended: :o'nlyf; as illustrative and-not "as-limitative: f"

In; radio? ll eeiving-l sets; generally 3 and more? particularly in the less 'expens'ive-setspi great difiicult'y is encountered: in gtheyrcepe :J' tion fro'mlstations' at atdistancfe and .B VIiy in stations close by, due: among {other things)? to 'a. lack of? sharptuning capabilities in: 2- the parts: of such sets and among. thefimorer important objects Tof this invention: 'is the provision; of -;a receiving set which av'vhile simple in construction andF-roperation and. inexpensive in cost is nevertheless capable: offvery sharp andquick tuning andvery efticient'detuning. Hi6;

j Where such receivingi apparatus employs the inductive relationship-0f! twol induc-- tion members. such as coi1s;it;jis obvious that the-efliciency ofthe inductance will be dependentupon the extent to which the secondary cuts the lines of force about the prilnary and this is a prime consideration in the mounting of induction members.

Among other important obj cots of my invention therefore are; the provision of a circuit for the reception of electric im pulses at radio frequencies which is simple in character and of a hook up which is eflicient in operation and cheap to manu-.

facture; the provision of a circuit for the reception of electric impulses at radio frequencies in which the grid leak condenser and secondary-are each connected directly to the variable condenser; the provision of inductance members so relatedand associated that the secondary may be positioned primary; the provision of inductance members so associated. as to permit of-their variation-inposition relatively to each other, so as to give maximum'inductance; the provision of inductance, members so arranged and associated as to" permit of rapid and-sharp tuning when employed as part of an apparatus for the reception ofelectric impulses at radio frequencies; the provision of inductance members so mounted and-associated as to-permit of the variation of their relative positions in more than one plane and-more particularly to permit of such variation by the operation of but one control; the provision'of inductance me'mbers so mounted and associated as to permit {of angular variation therebetween in fiat or spider web coil-having one of its :ffiatfaees provided With'an insulating covering; the provision of: relatively movable induction members; one offlwhich IS in the form of a flat coil covered on one side with insulation the other side being positioned adJacent the other member and more particnlarly of such a coil tapped through the insulation; and'tlie provision generally of a new and simplified receiving apparatus and of a new improved and'inexpensive arrangement of induction coils therefor.

In attaining the objects referrvid to and gaining certain other benefits and advantages that will appear or that will be below pointed out, I have provided a conin any desired portion of the field about the ico Figure' 4 looking in .tlieidirection of-the arrows.- r

Upon yiewing-Fi'gure tl it will-be observed that I have here shown diagrammatically a recei'vingm paratus in": which- 10 is 'tlte antamra'y ll t e primary,= 12 1the= groundland 13 the -taps for tuning tlie antenna a'eir'cuitz; The secbndsary is illustrated "as; 15;16 lbeing the-variable condenser, 17 the-grid lead coirdenser-g 18"the detector-l lamp,- 19 thewA }bat'-' figures the primary coil as ta pped for tuningg it will "be-' und-ei'stood that: this is: not essentiabas the secondary ina betapped'im: stead or: both rna-y-bewtappe -'for t lils purposel It will tlIBIEfOlG' be understood; as this speoifieation is read that the showin in the drawing -ili this-respect is merely -il nstrative; a

As will=be observed on-viewing Figure 2, 1 employ i for l tuning i purposes the induction I members 25 and 26 the'semembeis being mounted for movement relativelywf each other in:a plurality ofiplanes andiin aplurality of dii-ecti0ns= as will 'be pointed ont presently;

The element 27 is intended to 'showa -por-" tionof the support'whieh for instanee-mav he one of the walls 'of a-container, whio r container may take any desired or preferred form. The induction members -25 and 26 may be supported from this 'wall'27, the in duction member ,25 beingillustrated as im moi-ably cnrried=thereby'anrlthe member 26* i as carried thereby 'for variation with refer-' enc'e'to the-member 251 As will'he understood of course, this relative variation be;- tween the'=two -induction members may he obtainedregardless -'of'-which' one is-moved and in fact'may'be obtnined=upon anactual 1 movement of both.'- A's-will beobserve'd npon viewing -F ignres-Q and 3 I'ha-ve shown 1 he induction I members '25 'and 26 supported in a pendant position,- the-advantages of which will be obvious.

The induction members 2:: and i 26' are preferablyin' the form of flirt onspiderweb coils 'the' fixed coil25 beingslrown Eon-purposes of illtistrationms the-primary .and the" movab1e-coil 26*as:the' secondary. For pui tapped-eoil with an insulatedcovering such asthatillustrated at 30 in Figure 2 on that face whichjs futhestremored from the other coil,"and have run the tapping leads 27 tlu'ouglgithis-tinsulation 30.

The other induction member 26 which in the:-drawi sis illustrated as the secondary, is supports for movement linearly and bedily toward 'and awa from, the other-minduew tiommembers 25-h ii vinimintedtformovement aloh t the-Brod 3Lwhie1-r-xinnturnais mounted or 'rotntion.:in:;the: bearingr32r which is; hinged .10 :thewframe for.- pivotal. movement laboutitheihorizonatalraxisfia The B linelmmbvementqof the coil 26 alon :tlrea'od 31 may be attained in any de torupre fenced mnnem'ascby =mcans of the"engaige menti between ltli': nut '34" and ltheiqthreaded portzionfifizi no It will-therefore biundeestoedlthat when the knurled portion*36 0f.'l2heu10d3]I-IlS rotated in the bearings 32 the inductiomcoilfld. willibe mowed angularly i arallehof. the-coil 25 =andftransversely of It ewmagsnetli'e fieldh thereabout: Fnrthermeme;=.when--the rodw3 1-: is moved nbout rthevihingemnipivot 33:,uthe: secondary 26" will beugiren-s aanmvement: which i is angularlyntoward rand faway from the c0il25= ln'atlfisamanner bywhe o eras. 1 tioniofi lthe singleicontrol handle-36 "amr: enabled to 've the induetiumanembers :all: relative positions so thabthe secondary'may be so'positionedzwith relationship to the various" orbions-of the: magnetic fieldzthat the desire "sharp =tuningmnd-detunin may -be'-- quickly and simplyattained." It :willzbe nn dersto'od that 'both I movements can begiven simultaneously and in fact: it Willbe' unden stood thart omwof tho great advantagesziof- -this=anrange'ment is-not onlythat the=magnetic: field 'can be searched I quickly and elliciently but==that the secondary can be: given any *desiredi angular :position therein.

In:Figures=:'l'and 5 I have-shown-a modified construction for attaining the-de'sired variability between the induction I members in which the bearing member 32' iS supported'as showruin :Fi'gu're 5;-

I' havefound' that; by arrang'mg the coils as set forth; not only isanydesiredcharac-- ter'of inductance attained, but any point -in" the" magnetic 'field of the primary can -bequiekly'reached by-thebperatiomof the single' eontrol=36;.

The employment-of the pancake -coil% in sula'ted by'tho shield 3O and tapped'as shown adds materially to thesimplicity of the construction'andi to the good results attained by me.-- I have further found-thereby winding the coils 25 and 26 in opposite directions, I attain results which generally are better than those attained when the coils are wound in the same direction.

Having thus described my invention and illustrated its use, what I claim as new and desire to secure by Letters Patent is:

1. In an inductance mounting, the combination with an inductance member, of a second inductance member, and means whereby said second member may be shifted angu larly both transversely of, as well as toward and away from the field about said first member.

2. In an inductance coil mounting, the combination with an inductance coil of a second inductance coil, and means whereby said coils may be shifted relatively both parallel of each other, and angularly bodily toward and away from each other.

3. In an inductance coil mounting, the combination with a flat coil, of a second flat coil, and means whereby said coils may be shifted relatively both angularly parallel of each other and angularly bodily toward and away from each other.

4:. In an inductance coil mounting, the combination with an inductance member of a second inductance member, and means whereby said members may be shifted relatively bodily angularly of each other in a plurality of planes.

5. In an inductance coil mounting, the

combination with an inductance coil of a second inductance coil, and means whereby said coils may be shifted relatively bodily angularly of each other in a plurality of planes and linearly toward and away from each other.

6. In an inductance coil mounting, the combination with an inductance member, of a second inductance member, and means whereby said second member may be shifted angularly, both transversely of, as well as toward and away from the field of said first member, one of said inductance members being in the form of a flat coil.

7. In an inductance coil mountin the combination with an inductance mem er of a second inductance member, and means whereby said members may be shifted relatively bodily angularly of each other in a plurality of planes, one of said members being in the form of a flat coil.

8. In an inductance coil mounting, the combination with an inductance member of a second inductance member, and means whereby said members may be shifted relatively bodily angularly of each other in a plurality of planes, and a single control for giving said second member its different movements.

In testimony whereof I have hereunto signed my name.

CHARLES A. BIRCH-FIELD. 

